Physical compatibility of Xuebijing injection with 53 intravenous drugs during simulated Y-site administration

Objective Xuebijing injection (XBJ) is a commonly used herbal medicine injection in China. However, the physical compatibility of XBJ with other intravenous drugs remains unclear. The purpose of this research is to evaluate physical compatibility of Xuebijing injection (XBJ) with 53 intravenous drugs (including 31 Chinese medicine injections and 22 chemicals) during simulated Y-site administration. Methods Y-site administration was simulated in vitro by admixing 0.33 ml/ml XBJ with an equal volume of other diluted 53 intravenous drugs, respectively. Physical compatibility including visual inspection, Tyndall beam, particle limits, turbidity, pH, chromacity value, spectroscopic absorption of 550 nm and 420 nm (A550 nm and A420 nm) were observed and assessed at 0, 1, 2, and 4 h. Physical compatibility was defined as all solutions with no color changes, no gas evolution, particulate formation and no Tyndall beam within 4 hours, turbidity changes <0.5 nephelometric turbidity unit (NTU) compared to 0 h, particle limits allowed by the Chinese Pharmacopoeia (Ch.P) 2020 edition, pH changes <10% compared to 0, chromacity value changes <200 compared to 0 h, or photometrical changes of A420 nm <0.0400 or A550 nm <0.0100 compared to 0 h. Results XBJ was physically incompatible with 27 of the 53 intravenous drugs tested, 26 were compatible with XBJ for 4 h. Conclusions XBJ should not be simultaneously co-administered with 27 of the 53 intravenous drugs during simulated Y-site. If coadministration was inevitable, flushing tube with NS or D5W before and after infusion of XBJ was needed. Assessment included visual inspection, Tyndall beam, turbidity measurement, particle counts, pH measurement, chromacity value measurement and absorption of A550 nm were proved to be valid and robust for the quality control of infusion and compatibility of Chinese herbal injection.


Introduction
Xuebijing injection (XBJ) is a yellow or brownish-yellow clarified liquid mainly comprising of Honghua (Flos Carthami), Chishao (Radix Paeoniae Rubra), Chuanxiong (Rhizoma Chuanxiong), Danshen (Radix Salviae Miltiorrhiae) and Danggui (RadixAngelicae Sinensis) [1], the excipients are glucose, polysorbate 80 and water for injection.It was licensed in 2004 by the National Medical Products Administration (NMPA, China) [2] and approved for warm and heat diseases, such as fever, shortness of breath, palpitation, irritability and other syndrome of stasis and poison, to treat patients suffering from systemic inflammatory response syndrome induced by infection, combining therapy with the treatment of multiple organ dysfunction syndrome in the period of organ dysfunction.It can also treat severe and critical systemic inflammatory response syndrome and/or multiple organ failure of novel coronavirus infection.
As a commonly used herbal medicine injection in China, XBJ has been administered to critically ill patients for over 15 years.Extensive studies and clinical research have revealed its functions in sepsis [2][3][4].The injection exhibits protective mechanisms by antagonizing endotoxins and inhibiting the uncontrolled release of inflammatory mediators from endotoxinstimulated monocytes/macrophages.Additionally, XBJ improves coagulopathy in disseminated intravascular coagulation, an important risk factor for sepsis mortality [5].In China, over 250,000 patients receive XBJ treatment annually [6], and its route of administration and safety are well-established.The multiple positive clinical effects of XBJ make it an essential drug for critically ill patients.However, managing the coadministration of multiple drugs, especially those requiring prolonged intravenous infusions, along with XBJ can present challenges.
Due to limited independent catheters for central venous catheters [7], infusions should be ceased and the line flushed before administering other drugs [8].However, frequent stopping and flushing may affect the patient's fluid balance [9].Y-site access enables simultaneous intravenous drug coadministration but can lead to physical incompatibilities between drugs.Our main interest lies in the physical compatibility of XBJ with other intravenous drugs through Ysite.The quality and safety of co-administering XBJ with intravenous drugs remain unclear.This study investigates the physical compatibility of 53 commonly used intravenous drugs (31 Chinese medicine injections and 22 chemicals) with XBJ during Y-site administration.Methods used include visual inspection, Tyndall beam, particle limits, turbidity and pH changes, chromacity value changes, and spectroscopic absorption at 550 nm and 420 nm over 4 hours.Determining physical compatibility between XBJ and other intravenous drugs via Y-site could enhance safety management, reduce nursing time, and improve clinical utility.Additionally, we evaluated the sensitivity of these methods for scientific and feasible compatibility testing of Chinese herbal injections with other intravenous drugs to enhance infusion quality control.

Sample preparation
Under aseptic and laminar air flow conditions, the selected 53 intravenous drugs were diluted in NS or D5W as recommended by the manufacturer, a total of 50 ml XBJ was slowly diluted in either NS or D5W to a concentration of 0.33 ml/ml.Selected drug solutions were slowly added into the diluted solution of XBJ, respectively.Each of sample solutions was passed through a 0.5 μm filter, XBJ solution and selected drug solutions were gradually combined during a single test, followed by mixing the resulting solutions with a plugged glass tube or an empty venous infusion bag at a 1:1 ratio.The final concentration of the mixed solutions was half that of a single drug.
All solutions were gently inverted three times at room temperature (approximately 22˚C) at 0, 1, 2, and 4 h to ensure complete mixing.The solutions were then allowed to stand briefly or subjected to ultrasonic defoaming for 1 min.Physical compatibility including visual inspection, Tyndall beam, turbidity, particle counts, pH, chromacity value, A 550 nm and A 420 nm were observed and assessed intervals 0, 1, 2, and 4 h.Drug particulars, manufacturer, specification, lot number, diluent and concentrations were recorded for each drug (Table 1).

Experimental controls
2 negative control solutions containing 0.33 ml/ml XBJ in D5W and 0.33 ml/ml XBJ in NS, 4 positive control solutions containing 2.5 mg/ml calcium chloride with 0.0025 ml/ml composite potassium in NS, 10 μm latex particles reference material and 25 μm particle count reference material (Haianhongmeng reference material technology Co., Ltd, Beijing, Lot: 20221003 and L693, respectively) were used as control solutions to ensure the test results in experiments.

Visual inspection
According to Part 4 of the Chinese Pharmacopoeia (Ch.P) 2020 edition, using the "Solution Color Test Method" and "Clarification Test Method" [10], at each test point, all solutions were examined using a clarity tester on both black and white backgrounds with the naked eye.Visual incompatibility was defined as color changes, gas evolution, or visible particulate formation within 4 hours.

Tyndall beam assessment
Tyndall beam was assessed using a red laser pointer (650 nm, 50 mW) on both black and white backgrounds.Any sample prevented the light from passing through the solutions and appearing Tyndall beam was considered incompatible [11,12].

Turbidity measurement
Turbidity was measured at each time point through laboratory-grade turbidimeter (INESA Physico optical instrument Co., Ltd, Shanghai) according to the instructions.Three repeated measurements were taken for each sample, using the average as the final result.Physical incompatibility was defined as turbidity changes �0.5 NTU compared to 0 h [13,14].

Particles measurement
Particle counts were counted using the GWF-8JA Particle Counter (Tianjin Tianhe Analysis Instrument Co., Ltd, Tianjin).Part 4 of the Ch.P recommended that injectable solutions be analyzed using a light obscuration particle count test.According to the Ch.P, for injectable solutions labeled as �100 ml, the number of �10 μm particles shall not exceed 25 particles/ml, the number of �25 μm particles shall not exceed 3 particles/ml [10].Three repeated measurements were taken for each sample, using the average as the final result.

pH measurement
pH was measured to assess whether acid-base reactions may involve any observed incompatibilities.The same time points mentioned above (intervals 0, 1, 2, and 4 h), pH of solution were determined using a pH meter (Qiwei instrument Co., Ltd, Hangzhou).Any solutions with pH variations <10% compared to the baseline (immediately after mixing) were considered incompatible [15].

Spectroscopic measurement
The Spectroscopic measurement was performed using 8453 Hewlett Packard diode array ultraviolet visible spectrophotometer to detect any indications of color change (A 420 nm ) or haze (A 550 nm ).All solutions were considered incompatible if the absorption changes by A 420 nm >0.0400 or A 550 nm >0.0100 [16].

Statistical analysis
Descriptive statistics and original data were presented.Results of particle count were reported as mean ± standard deviations (mean ± SD).No further statistical analysis was performed.

Definition of compatibility
Justification of compatibility refers to the diagram in Fig 1 .Physical compatibility was defined as all solutions with no color changes, no gas evolution, particulate formation and no Tyndall beam within 4 hours, turbidity changes <0.5 NTU compared to 0 h, particle limits allowed over the Ch.P, pH changes <10% compared to 0, chromacity value changes <200 compared to 0 h, or absorption changes by A 420 nm >0.0400 or A 550 nm >0.0100 compared to 0 h.

Visual inspection and Tyndall beam findings
No visual changes (color changes, gas evolution, haze, or visible particulate formation) were detected over the 4 hours period for the solutions (Table 2).However, the combination of XBJ + Acyclovir sodium, XBJ + Ceftriaxone sodium, XBJ + Cefuroxime sodium, XBJ + Iprazole sodium and XBJ + Rabeprazole sodium solutions in NS displayed Tyndall Beam, respectively (Fig 2 ), indicating that XBJ was incompatible with above 5 drugs.

Turbidity changes findings
The results from turbidity measurement were summarized in Table 2. Of the 53 selected drugs, combinations of XBJ + 51 drugs result in turbidity changes <0.5 NTU compared to 0 h, respectively.At the time of 1, 2, 4 h, combinations of XBJ + Iprazole sodium and XBJ + Rabeprazole sodium solutions displayed turbidity changes >0.5 NTU compared to 0 h.It indicated that XBJ was incompatible with Iprazole sodium and Rabeprazole sodium.Rabeprazole sodium, respectively.Then showed a increase within the 0 to 4 h in our study.The particles in above solutions exceed the recommended the limitation of the Ch.P specification.At the time of 4 h particles in group of XBJ + Tanreqing injection and XBJ + Cefazolin sodium also exceed the limitation of the Ch.P, indicating that XBJ was incompatible with above 19 drugs.

pH changes findings
Table 3 exhibited pH range of combinations of XBJ with other intravenous drugs (4.0 to 10.0).pH changes that did not vary >10% from baseline (immediately after mixing) in any admixture.

Chromacity value changes findings
Table 4 exhibited XBJ had no change in color visually and chromacity value �700 within 4 h with the selected 53 intravenous drugs mixing solutions.It inferred that the chromacity value change of 1, 2, 4 h were <200 compared to 0 h, two drugs were physically compatible.

Photometrical changes findings
Absorption at 550 nm were detected.Binary combinations of XBJ with Danshen Chuanxiongqin injection, Guanxinning injection, Kang'ai injection, Kuhuang injection, Tanreqing injection, Xiangdan injection, Xueshuantong for injection, Ceftriaxone sodium, Cefuroxime sodium, Ganciclovir sodium, Ilaprazole sodium, Lansoprazole sodium, Omeprazole sodium, Pantoprazole sodium, Rabeprazole sodium solutions immediately displayed A 550 nm changes >0.0100 compared to 0 h and combinations of XBJ with Extract of Ginkgo Biloba Leaves, Qingkailing injection, Yinxingneizhi injection, Aciclovir sodium, Doxofylline, Magnesium Sulfate solutions displayed A 550 nm changes >0.0100 at 4 h compared to 0 h (Table 4), the results showed that XBJ was incompatible with above 21 drugs.Binary combinations of XBJ with 53 intravenous drug solutions were primarily yellow or brown-yellow in appearance.The range of A 420 nm varied from 2.8000 to 4.1000, resulting in a significant error.The change in A 420 nm exceeded 0.0400 (Table 4).

Discussion
XBJ infusion was usually administered clinically within 4 hours.In this study, the physical compatibility for XBJ in binary combinations with selected 53 intravenous drugs were evaluated.Table 2 showed that no visual changes (color changes, gas evolution, haze, or visible particulate formation) were detected over the 4 hours period for the solutions.However, the combination of XBJ +Acyclovir solutions, XBJ + Ceftriaxone sodium, XBJ + Cefuroxime sodium, XBJ + Iprazole sodium and XBJ + Rabeprazole sodium solutions in NS produced Tyndall Beam respectively (Fig 2 ), indicating that XBJ was incompatible with above 5 drugs.Since the discovery of the Tyndall effect, it has been mainly used to assist the observation of the effect of colloidal solutions in experiments.As a control index of solution properties for intravenous drugs, Tyndall effect can directly reflect the solution quality and physical compatibility of intravenous drugs without damaging the package of drug solutions [11,12,17].In our study, three inspections of color change, clarification and Tyndall effect were used to evaluate the properties of solutions, and it was compared with 10 μm latex particles material, 25 μm particle count reference material and mixed solution of Calcium Chloride with Composite Potassium, which could produce Tyndall effect.It was proved that Tyndall effect could be used as an inspection method of solution properties and physical compatibility of Chinese medicine injection.Three inspections can objectively reflect the quality of the solution of Chinese medicine injection.However, our studies found that oily Chinese medicine fat milk injections such as Brucea Javanica oil emulsion injection, Elemene injectable emulsion and Zedoray Turmeric oil injection can produce Tyndall beam, which is not suitable for this inspection method.The inspection of these kind of intravenous drug solutions need further study in our research.
The turbidity of the solutions can be measured by a turbidity meter.Different size and qualitative of particle matter in solutions can scatter the incident light.The turbidity of the solutions can be checked by measuring the intensity of the transmitted or scattered light.The transmitted-scattered light comparative measurement model is used for the turbidity determination of low and medium turbidity colorless solutions (turbidity below 100 NTU).The colored substance may reduce the turbidity of the solution, but yellow has the least effect on the results [18].The diluted solution of XBJ was a yellow solution, 31 kinds of traditional Chinese medicine injection were mainly yellow clarified liquid, 22 kinds of intravenous drug solutions were colorless or almost colorless clarified liquid.The combination solutions of XBJ with other 53 drugs solutions were mainly yellow or browish-yellow clarified liquid, which was also suitable for turbidity determination.The turbidity change of the solution can avoid the possible influence of color on turbidity, and physical incompatibility was defined as �0.5 NTU change in turbidity compared to 0 h [13,14].From above tests we found that XBJ was incompatible with Iprrazole sodium and Rabeprazole sodium.Part 4 of the Ch.P recommends that injectable solutions be analyzed using a light obscuration particle count test [10].For this study, XBJ with Danshen Chuanxiongqin injection, Dengzhanxixin injection, Guanxinning injection, Kang'ai injection, Kuhuang injection, Qingkailing injection, Shenfu injection, Xingnaojing injection, Xueshuantong for injection, Aciclovir sodium, Cefoperazone sodium and Sulbactam sodium (1:1), Ceftriaxone sodium, Cefuroxime sodium, Composite Potassium Hydrogen Phosphate, Ganciclovir sodium, Ilaprazole sodium, Rabeprazole sodium solutions result in particles exceed the limitation of the Ch.P immediately after mixing and also after 4 hours.The particles in XBJ + Tanreqing injection and XBJ + Cefazolin sodium solutions exceed the limitation of the Ch.P at the time of 4 h, indicating that XBJ was incompatible with above 19 drugs.Interestingly, Tyndall Beam presented in the combination of XBJ + Acyclovir sodium, XBJ + Ceftriaxone sodium, XBJ + Cefuroxime sodium, XBJ + Iprazole sodium and XBJ + Rabeprazole sodium groups, indicated that exceed the limitation of particles might produce Tyndall Beam.During the test, XBJ and select drug were slowly diluted in NS or D5W respectively, mixed slowly along the bottle wall to avoid air bubbles affecting the count of particles.If bubbles are formed, solutions were recommended to stand briefly or subjected to ultrasonic defoaming for 1 min.It was found that XBJ diluted with NS or D5W with concentration �0.5 ml/ml might result in exceeding the limitation of particles and produce Tyndall Beam.Thus, it was recommended to use XBJ concentration �0.33 ml/ml clinically.Our pre-experiment found that particles counts were not suitable for the quality control of oily Chinese medicine injectable emulsion such as Brucea Javanica oil emulsion injection, Elemene injectable emulsion and Zedoray Turmeric oil injection, which were suitable for "Determination of particle size and particle size distribution method".The further studies will conduct in next stage.
Studies reported that pH changes of intravenous drug solution within the range of 0.2 to 1.0, the solution was stable and compatible [19][20][21][22].Dotson et al. defined physical incompatibility as a pH value of no more than 10% change from baseline (0 hour) after 48 hours [15].For our pH measurements (Table 4), all solutions were within the range of 4.0 to 10.0.Compared with 0h, if the pH value of the solution changes by 10%, the pH result will change within 0.4~1.0accordingly.We intentionally to select the stricter pH changes defined as <10% to confer compatibility in our study, and all solutions had pH change <10% over the time of test.Compare to visual measurement, using a colorimeter to determine the chromacity value of the solutions have advantages in accurately and quantitatively.However, turbid solutions, viscosity solutions or fluorescent solutions will affect the transmission of the inspection light, they are not suitable for chromacity value measurement.Binary combinations of XBJ with selected 53 intravenous drug solutions are clear, non-viscous, non-fluorescent liquid, so it is suitable for chromacity value determination.From results in Table 4, chromacity value of all solutions were �700 and had no change in color visually with 4 h.We inferred that the chromacity value changes are less than 200, two drugs were considered physically compatible.Based on previously published literatures, colorless, almost colorless or lightly colored drug solutions were considered compatible if A 420 nm <0.0400 [16,19].Generally, the absorbance of test solution falls between 0.3 and 0.7, indicating a small margin of measurement error.Binary combinations of XBJ with 53 intravenous drug solutions were primarily yellow or brown-yellow in appearance.The range of A 420 nm varied from 2.8000 to 4.1000, resulting in a significant error.The change in A 420 nm exceeded 0.0400 (Table 4).The results indicated that criterion of A 420 nm was not suitable for physically compatibility of our study.The light transmittance of water for injection at A 550 nm is 100% and the absorbance is 0. Studies reported that drug solutions were considered compatible if A 550 nm <0.0100 [16,19].21 drugs were incompatible with XBJ during the test.
Due to the lack knowledge on drug incompatibility issues and ways on how to avoid them, incompatibility is often under-recognised by health care practitioners.Incorrect processing with incompatibility events will bring consequences for workload, infection and cost [23].How to handle y-site the situation need more studies to explore and verify.However, when coadministration is inevitable, flushing or filter is needed [24].Chinese medicine injections primarily consist of water extracts from complex Chinese herbs.During storage and application, the insoluble particles can increase, which may pose potential risks.To ensure the safety of these injections, it is advisable to use a disposable precision filter infusion set with a 5.0 μm diameter before intravenous infusion.Additionally, proper storage conditions should be maintained to prevent contamination by microorganisms, ensuring the physical, chemical, and pharmacodynamic stability of the drugs.However, chemical and pharmacodynamic measurements are time-consuming and limited by instruments and experimental conditions, which do not meet the requirements for obtaining rapid results.Therefore, the evaluation of Chinese medicine injections should primarily focus on physical compatibility criteria, including visual inspection, Tyndall beam, turbidity, particles, pH, chromacity, and absorption at A550 nm.Nevertheless, considering chemical compatibility can provide further insights into the quality of the solutions.

Table 5 .
Description of XBJ physical incompatibilities with 27 drugs.co-administered with above 27 drugs through the Y tube.If coadministration is necessary, it is recommended to flush the infusion tube with an appropriate amount of NS or D5W before and after infusion of XBJ.The novel findings on the physical compatibility of XBJ broadens current knowledge of the safe coadministration of intravenous drugs clinically.It provides a safer infusion in ward.Additionally, we provide scientific and feasible methods for compatibility testing of Chinese herbal injection with other intravenous drugs for the quality control of infusion.These findings have significant implications for clinical practice.Tyndall positive = a, �10 μm particles exceed 25 particles/ml = b, �25 μm particles exceed 3 particles/ml = c, change of A 550 nm �0.0100 = d, turbidity increased by �0.5NTU = e https://doi.org/10.1371/journal.pone.0299694.t005

Table 2 . Findings of visual inspection, Tyndall beam, turbidity changes in solutions.
Yellow/Clear Yellow/Clear Yellow/Clear N N N N 0.106 -0.012 -0.014 -0.032 Comp Composite Potassium Hydrogen Phosphate Yellow/ Clear Yellow/Clear Yellow/Clear Yellow/Clear N N N N 0.056 0.035 0.022 0.019 Comp Danhong injection Yellow/ Clear Yellow/Clear Yellow/Clear Yellow/Clear N N N N 0.130 -0.042 -0.038 -0.046 Comp Danshen Chuanxiongqin injection Yellow/ Clear Yellow/Clear Yellow/Clear Yellow/Clear N N N N 0.111 0.003 0.016 -0.009 Comp Yellow/Clear Yellow/Clear Yellow/Clear P P P P 0.295 1.362 1.755 2.422 Incomp (Continued )